1. FIELD OF THE INVENTION
The present invention relates to a magnetic head supporting device for supporting a magnetic head, especially, a small-sized thin film magnetic head.
2. DISCUSSION OF BACKGROUND
In the magnetic head supporting device of this type, the following requirements have to be satisfied in order that the thin film magnetic head can follow tracks formed in a surface of the magnetic disk with a predetermined small gap. Namely, a slider of the magnetic head which holds reading/writing elements undergoes a pitching motion with respect to a first axis and a rolling motion with respect to a second axis which perpendicularly intersects the first axis to thereby remove uneven swinging motions. Such magnetic head supporting device is disclosed, for instance, in U.S. Pat. No. 393164 and U.S. Pat. No. 4167765.
The conventional magnetic head supporting device disclosed in the above-mentioned publications is generally constructed as follows. A supporter comprising a resilient spring portion and a rigid beam portion formed integrally with the resilient spring portion is formed of a resilient metal plate such as a stainless steel plate. A flexible member formed also of a resilient metal plate such as stainless steel is attached to a free end of the supporter. A loading projection is provided either on the upper surface of the flexible member or on the lower surface of the supporter at a position near the free end so that a load is applied from the free end of the supporter to the flexible member. Then, a thin film magnetic head which holds a slider having reading/writing elements, is attached to the lower surface of the flexible member.
The magnetic head supporting device of this kind has a tendency that the size of a magnetic head is reduced in order to comply with demands of high density magnetic recording and quick recording. The miniaturization of the magnetic head is effective to reduce a flying height and a spacing loss which are necessary to achieve high density recording as well as to increase resonance frequency; to prevent crashing and to improve durability in association with a magnetic head supporter. Further, the miniaturization of the magnetic head facilitates the maintenance of an appropriate balance between a dynamic pressure and a spring pressure by the supporter, a good floating posture and the obtaining of stable floating characteristic. Furthermore, by reducing the mass of the magnetic head by the miniaturization allows the accessing movement at a high speed.
In the conventional magnetic head supporting device, there were the following problems.
(1) In order to obtain a magnetic head supporting device which effects a low flying height, it is necessary to reduce a dynamic pressure for lifting the magnetic head by reducing the surface area of the air bearing surface of a slider which is a part of the magnetic head. Since the conventional magnetic head supporting device comprises a flexible member constituted by a resilient metallic plate of a material such as stainless steel, the spring function of the flexible member is far stronger than the dynamic pressure for lifting the magnetic head which is produced at the slider, so that when a low flying height is to be obtained, it is difficult to balance the spring function to the dynamic pressure, and it is difficult to obtain a stable control of the posture of the magnetic head.
(2) In order to obtain good balance between the spring function of the flexible member and the dynamic pressure, it is necessary that the flexible member has a complicated shape and structure as described in the above-mentioned publications. However, since the flexible member is made of a resilient metallic plate such as stainless steel, it is difficult for the flexible member to have a complicated structure. In particular, when the size of the slider which is the major part of the magnetic head is made small, in order to achieve a low flying height, the size of the flexible member should also be reduced. Accordingly, the processing of the flexible member is also difficult.